Analysis of genes increases understanding of oil’s effects

New techniques in the field of genetic analysis are improving our understanding of the effects of oil spills.

Image of a colony of blue mussels on a shore in Larsen Bay, Prince William Sound. The waters and mountains of Prince William Sound can be seen in the distance.
The Council collects samples from blue mussels like these to better understand the effects of oil spills. Photo by Lisa Matlock.

Since 1993, the Council has gathered data on the presence of hydrocarbons in sediments and blue mussels in the region. Samples of sediments and mussels are collected and analyzed for the presence of oil or other pollutants that originate from the Valdez Marine Terminal and tankers that ship oil from there.

In 2019, the Council began looking at new methods to measure the impacts of oil on the environment. In April 2020, a spill from the terminal leaked approximately 1,400 gallons of oil into Port Valdez. This unfortunate incident presented a unique opportunity to learn.

The new research analyzes the genes of blue mussels using a technique known as “transcriptomics.” Transcriptomics involves measuring how particular genes are expressed in an organism. This expression can be affected by conditions in the environment.

The research began in 2019 with a pilot study. The early research looked at 14 specific genes. More recent work expanded the study to over 7,000 genes, and is summarized in a new report sponsored by the Council.

The researchers compared samples of mussels taken from sites near the terminal, near the Valdez harbor, and a third control site. They found some interesting results.

Effects of oil on genes lingers

After the April 2020 spill, the levels of oil in the mussels had declined by August, however the mussel’s genes showed evidence of lingering effects.

Different pollutants have different effects

More recently, researchers tried to identify how the effects differed according to different contaminants. The crude oil-contaminated samples were compared to samples from the Valdez harbor, which were contaminated with pollutants such as diesel fuel or vessel exhaust, and the control site.

Genes such as those associated with stress, neurotransmitters, and the immune system were among those that varied between the three sites.

Results expected to have far-reaching implications

The information in these studies will help improve the Council’s monitoring program in the future. The researchers noted in the report that the findings are not just applicable to Alaska but could potentially improve monitoring in marine environments around the world.

Alaska North Slope oil trending lighter since 2010

Photo take after the Exxon Valdez oil spill of a rocky beach in Prince William Sound. The rocks are coated in black crude oil.
The oil spilled in 1989 (pictured above) was “heavier” than the oil flowing through the Trans Alaska Pipeline today.

Crude oil is often referred to as a “fossil fuel” because it is made up of plants and animals that lived millions of years ago. Over time, these remains were exposed to heat and pressure inside the Earth’s crust, forming crude oil.

This process is full of variables. The organic materials that make up one pocket of oil can differ from another, or the deposit could have been exposed to different pressures or temperatures during formation. These variables mean oils have different properties such as density, viscosity (thickness), or tendency to form an emulsion.

The oil pumped through the Trans Alaska Pipeline System is a mixture from different fields. That mixture changes over time. The properties of oil can change as the field ages, and new fields are brought into production.

These variations mean the oil behaves differently. It can flow faster or slower, or evaporate more readily.

These, and other variations, influence the techniques used to clean up a spill.

Approximately every five years, the Council obtains a sample of crude oil from the Trans Alaska Pipeline System for analysis. Researchers look at properties such as weight, evaporation, and emulsification. A new report summarizes the latest findings.


A “heavy” oil is denser than a “light” oil, which flows more easily. Heavy oils are more useful for asphalt and plastics, while lighter oils are processed into gasoline and jet fuel.
When the pipeline first started transporting oil, the oil was considered “heavy.” In 2010, a sample analyzed by the Council found that the oil had lightened considerably. The trend continued in 2015 and again with this recent sample, although the shift has not been as dramatic since 2010. The most recent analysis categorizes the oil as a “medium” viscosity.

These properties may affect response tactics. For instance, if spilled, lighter oils may be easier to pump, however lighter oils could spread more rapidly, covering a larger area.


Lighter weight oils are made up of substances that evaporate more easily. A fuel such as gasoline can evaporate completely at temperatures above freezing. In crude oil, however, evaporation of lighter molecules leaves behind heavier components of the oil. The heavier oil components emulsify more readily.


Emulsification is the process by which one liquid is dispersed into another one in the form of small droplets. Mayonnaise is an example of an emulsion: oil, water, and egg yolks are whisked together to form a thick paste, with the egg serving as the emulsifier to keep the oil and water from separating. In a similar fashion, ocean waves and wind can mix water droplets into spilled oil.

Some emulsified oils break down and separate back into oil and water over time, however in heavier oils, this mixture can stabilize, becoming permanently emulsified.

Emulsified oil is much more difficult to clean up. The volume can triple in size and become almost solid. If the emulsion stabilizes, it is difficult or impossible to recover with a skimmer.

Oil samples analyzed by the Council prior to 2001 formed stable emulsions when weathered. Tests performed on the recent sample found that the newer oil will emulsify, but does not stabilize into a permanent emulsion.

Report available online

The tests on the sample were conducted by Environment and Climate Change Canada. Dr. Merv Fingas interpreted the lab results, which are summarized in the new report:

Archibald: The power of ‘our’: Overcoming challenges by owning responsibilities

Robert Archibald, President of the Council’s Board of Directors

Oh, how time flies. It has now been just over 34 years since the Exxon Valdez oil spill. So much time has passed, but I still believe there is something to learn every day.

The Council recently released a report detailing accounts of unacceptable safety risks at the Valdez Marine Terminal. We hope this report provides an opportunity for the Council, industry, and regulators to work together to address any substantial safety issues at the terminal.

With new oil development on the horizon, every effort must be made to ensure the integrity of systems and infrastructure within the Trans Alaska Pipeline System, including the Valdez Marine Terminal.

The issues and recommendations covered by the assessment and report will take some time to address. The Council stands ready to support Alyeska, and state and federal regulatory agencies. As we move forward, the Council plans to conduct outreach within our region to share opportunities, as they arise, to help ensure that the key findings and recommendations in the report are addressed. We must do everything we can to protect our people, communities, economies, and our environment from another major oil spill.

Thinking about the Council’s duties and responsibilities during these challenging times brought to mind comments I heard at a recent Homer community meeting on defining moments. A long-time resident stood up and proceeded to give her thoughts about an endemic problem with modern society. It is the use of the word “the,” instead of the word “our.”

Just sit back and think how the word “the” is used today. The problem, the government, the city, the laws, the regulations, the schools, the responsibility, the resources… I could go on, but you get the point. Consider instead if more people made a conscious choice to use “our” instead. Taking ownership of challenges instills a more dynamic participation in our modern problems.

A small shift with giant results.

The Council was born out of a lack of responsibility on OUR part: industry, government, and public. In 1989, our government and industry were unprepared. While some concerned citizens were trying to raise alarms about the risks of a spill, many folks in our communities were unaware of the danger. The Council was formed to combat the complacency that unfortunately led to the Exxon spill and inform the public about issues that impact the safe transportation of oil through our region, with the goal preventing future spills. We must ensure that the successes we have helped achieve since our formation continue to move forward. This can be extremely challenging in our current environment of budget cuts and staffing reductions within industry and regulatory agencies.

Winston Churchill once said, “Success is not final.” The legacy of those that lived through the Exxon spill and fought to form this citizens council carries on in our work today. Their work – now our work – must continue as long as oil flows through the pipeline.

The Council is a voice for the people, communities, and interest groups in the region oiled by the Exxon spill. Those with the most to lose from oil pollution must have a voice in the decisions that can put their livelihoods and communities at risk. Our common goal with industry and regulators is to help maintain and improve safe operation of the Valdez Marine Terminal and associated tankers.

We hope that, years from now, we can look back at actions taken as result of this report release and see that they created another great success in the history of the safe operation of the Valdez Marine Terminal and our spill prevention and response system. We hope this will be another example of citizens, industry, and regulators working together to prevent future oil spills.

After all, we are ALL in this together – to protect our livelihoods, our communities, and our environment.

Let’s do it right.

Terminal operations lead moves on; new project manager joins team

Austin Love, who has managed the Council’s projects related to the operation of the Valdez Marine Terminal is moving on. Love has been working part-time since December to support the Council’s projects until a replacement could be found.

Austin Love

Love worked with both the Terminal Operations and Environmental Monitoring Committee and the Scientific Advisory Committee on a variety of projects. Love has been praised by coworkers and volunteers alike for his skill at communicating technical content to general audiences. During his time with the Council, he co-authored several research papers for projects such as the recent transcriptomics analysis, part of the Council’s Long-Term Environmental Monitoring Program. 

Sadie Blancaflor

Love’s replacement, Mercedes “Sadie” Blancaflor, joined staff in May of this year. Originally from Baltimore, Maryland, Blancaflor holds a Master of Science in Earth Systems from Stanford University, and she previously taught Environmental Law as an Adjunct Professor at the University of Alaska Fairbanks.

“Austin was a fast learner and focused advocate for the environment in his role at the Council, and he will be greatly missed,” said Executive Director Donna Schantz. “I am pleased that Mercedes has joined the team and look forward to working with her in her new role.”

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